TRS-80 Emulation: Disk Conversion Instructions

Modern hardware and operating systems are making it more difficult to convert actual TRS-80 disks into an emulator (DMK or DSK) format.

Some of the obstacles are:

No ability to read single density disks whatsoever

Current operating systems do not allow for direct hardware addressing

No 5.25″ drive support in the BIOS

Pure Double Density TRS-80 Disks (Model III, 4 and 4P)

While you can you can always send the diskettes to me to convert, if you wish to try to convert Model III, 4 or 4P disks yourself, you will need:

A 5.25″ disk drive (obviously); and either

A very very very old PC (i.e., IBM PC/AT, PC/XT, or the like) to get BIOS Support

The appropriate software (below on this page)

Single-Density or Mixed Density (Model I) other than TRSDOS and NEWDOS/80

Reading single-density disks (which is what the Model I used; noting that even double density disks tended to have a single density track 0) is MUCH more complicated. “Modern” computers do not have the crystal needed to generate a single density clock, so they simply cannot read single density. Even those that can will have trouble with TRSDOS 2.x (DAM problem) or NEWDOS/80 v1.x (DAM problem) or NEWDOS/80 v2.0 (Inner Track Problem).

To convert Model I disks (other than TRSDOS or NEWDOS/80) to emulator format you can send the diskettes to me or you will need:

A 5.25″ disk drive (obviously); and either

A PC with an ISA port and any of the following
The Adaptec 1522 SCSI controller (ISA, non-bus-mastering, NS8473 Controller) can read/write/format FM (Single Density) floppies, including LDOS-format SD floppies. TRSDOS2.3 directory tracks CANNOT be handled on these because of the DAM.
It is possible that the Adaptec 1542 SCSI controller (ISA, bus-mastering, NS8473 Controller)
The Acculogic ISApport SCSI adapters (SMC FDC37C65) will read 360K Double Density but will not read single density on a 1.2MB HD drive.

A working TRS-80 Model I (where you would then copy the files to a more friendly OS like LDOS)

A working TRS-80 Model III or 4 (where you would then copy the files to a double density operating system)

WARNING!!!!

Before putting a disk in your drive, make sure to inspect it. Improperly stored disks will degrade, and will shred in your drive. Inserting one of these disks in your drive will not only produce a disheartening noise, but will likely coat your read/write head with oxide, requiring you to clean the heads. Here are some pictures I took of some of these improperly stored or otherwise decayed disks. Click on the images for more detail:

Reading/Writing TRS-80 Disk Media on a PC

If you have a 5.25″ drive hooked up to your IBM PC, the following programs can be used to read TRS-80 disks into the DMK/DSK format. If you want to read Model 1/3/4 disks and have a Catweasel card, use Tim Mann’s CW2DMK utility. If you want to read Model 1/3/4 disks and do not have a Catweasel card, use Matt Read’s READDISK utility. If you want to read COCO disks, use Jeff Vavasour’s RETRIEVE utility.

READDISK transfers files from a TRS-80 Diskette to an IBM .DSK file without special equipment. This version can also read Tandy 1000 disks.

Please note that not all PC disk controllers are capable of reading TRS-80 disks. This is a limitation of the disk controller, not READDISK. If you have trouble, try running READDISK on other PC’s until you find one that can read your disks. Remember, you only need to read your TRS-80 disks once to convert them to disk images, so be sure to use the “Retry” command heavily.

Please note that not all PC disk controllers are capable of reading TRS-80 disks. This is a limitation of the disk controller, not READDISK. If you have trouble, try running READDISK on other PC’s until you find one that can read your disks. Remember, you only need to read your TRS-80 disks once to convert them to disk images, so be sure to use the “Retry” command heavily.

The following programs are over a decade old and regardless of whether or not they even work, the above are much better choices at this point in time.

The TRS-80 Model 4 Emulator’s virtual disk utilities have been provided free for download in order to allow you to determine whether your PC has the features necessary to read and write TRS-80 floppies directly. The emulator can either access your TRS-80 floppies directly in its floppy drive, or as images copied to your hard drive. Either way, you need to be able to determine whether the PC hardware can read the floppies.

This is actually here because many kind people have asked if I wanted them to scan certain items in their collection. To avoid the various searching for prior sent emails, the following is a list of pointers and requests when scanning for the site:

Scanning Modes:

Color pages should be scanned in True Color

Non-Color pages should be scanned in full grayscale … NEVER in “BITMAP” or “Black and White”

Images should be scanned in at LEAST 400 DPI

Images should be saved as non-compressed TIFF’s. NEVER as JPEG’s.

Processing:

Make sure the text is more or less straight … if its at a sharp angle, please re-scan the page.

Make sure each page size is the same dimension. Note: Rotating a scan in an image editor, rather than doing the re-scan, will change the scanned page dimensions.

Trim off any unintended dots at the margins. Jagged edges, overscans, etc., all take up space in addition to being useless. If clear those stray items, the pages will look nicer AND will take less space.

Note: If you cannot do the “Processing” part, then I will do it for you, but will need the TIFF’s. I can set up a temporary FTP site for you to upload to if you contact me.

I have a TRS-80 Color Computer 3 and an original color computer disk drive, and I got my cassette programs onto disk on my own. However, I have no clue how to get my programs from the floppy disks into a virtual format that I could preserve on modern equipment, and I really wish I could do that. I do have a late 1980s/early 90s DOS/Windows 3.1 PC with a 5 1/4 floppy and a 3.5 floppy, and a late 1990s PC with a 3.5 floppy and a CD-R/W, and a couple of newer machines. But the PC could not read the TRS-80 disks, which I imagine is a problem of format but I am not up on these things. My programs are all basic and I saved them in ASCII format, but I’m guessing the problem is deeper than that. If you have the know-how and the equipment, I’d be happy to pay for a conversion of my disk (I have one disk to convert, at most I may have a second one but as of now I just have one). Thoughts?

Hello I have hundreds of 5 1/4 Double Density floppies formatted for MS DOS. I would like to have these converted to a contemporary media, is it possible? It’s for an archive project for a writer.
Thank you

Important Note:

Is there an eBay store for TRS-80's?

Yes - Three

Dale Frantz has had his "TRS80sAndMore" store on eBay for 18 years, with 100% positive feeback and 100% money back guarantee. Check out the store HERE!.
Trash Talk Podcaster Ian Mavric has also been on eBay for more than 18 years also with 100% feedback and a long history with TRS-80s going back to the 1980s. Timely, reliable shipping from Australia. Check out the store HERE!.
Bra McCartney also has a Store.

Do you have TRS-80 Disks or Tapes?

If you have Model I, III or 4 TRS-80 disks lying around, you may want to think about sending them in. If the data is intact, I can read them into “virtual disk files” (DMK files) which will serve not only to archive the disk forever, but would also allow you to use those virtual disks in an emulator on your current computer, and to extract the data to your current computer if you wanted to.

The media on these disks and tapes were not intended to hold data for 35+ years and the data will not last forever. If you do have disks lying around, I would encourage you to contact me.